Electric resistance



Yi 11930- c. s. HAWLEY 1,760,057

ELECTRIC RESISTANCE Filed Feb. 26, 1927 INVENTOR CORNELL s. HAWLEY BY 5W, P

ATTORNEY Patented May 27, 1930 I UNITED STATES PATENT OFFICE CORNELL S. HAWLEY, OF ALBANY, NEW YORK, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO CONSOLIDATED CAR-HEATING COMPANY, INC., 01 ALBANY, NEW YORK, A COR- PORATION OF NEW YORK ELECTRIC RESISTANCE Application filed. February 26, 1927. Serial No. 171,235.

For a detailed description of the present self of insulating material. By virtue of the form of my invention, reference may be had fine wire wound on the outside of this cord to the following specification and to the acit becomes sufiiciently stiff to hold its shape companying drawing forming a part therewhen wound into a helix of small diameter.

of, wherein This helix can then be coiled on a porcelain 0 Fig. 1 shows my resistance in perspective core and secured thereon, preferably by and means of an uncoiled insulating cord Fig. 2 shows a section thereof in enlarged threaded through it axially.

detail. Thus in the accompanying drawin A My invention relates to an electrical rerepresents the fine bare wire, devoid 0 any 5 sistance and is particularly designed as an insulating coating but wound on an insulatimprovement on the resistance shown in the ing cord B which is itself soft and limp as United States patent of Claude C. Nuckols contrasted with the support-wire of Nuekols and Frederic Pruyn, No. 1,019,075, dated and Pruyn, but is externally stiffened to a March 5, 1912, which has been heretofore degree by the fine wire wound around it. The used. My invention is directed to an eleccord B with the wire A thereon can then trical resistance in whichas in the patent be coiled into a helix of rather small direferred toan extremely fine wire is emameter which will hold its shape and a bindployed, such as is necessary for signalling ing cord C of insulating material passed and other apparatus used on electric railaxially through it. After the helix is seated way vehicles where the voltage is high and on the porcelain core D the binding cord is the amount of energy needed for the appadrawn taut and secured at its ends to the ratus is comparatively small. In resistances core. By this means the cord B becomes sufof this kind the fine wire is diflicult to inficiently stiff to stand up and carry the bare sulate and support by reason of its minute fine wire A. One advantage of my arrangediameter and lack of mechanical strength, ment is that there is no metal in the supportwhile it is also difficult to handle it without ing cord, so that the danger encountered in breaking it. the Nuckols and Pruyn structure, of the This difficulty was met in the Nuckols and enamel stripping off from the supporting Pruyn patent by winding the bare fine wire helix with consequent loss of insulation, is helically on a stiff insulated wire which was avoided. It is also cheaper and simpler in itself in the form of a helix helically wound addition to its greater reliability. on a grooved porcelain core. This wire was \Vhat I claim as new and desire to secure in the nature of a mechanical self-sustainby Letters Patent is ing support for the non-self-supporting 1. An electrical resistance comprisinga refine wire, and was insulated therefrom fractory core, a coreless insulating cord, a usually by some plastic coating baked hard bare resistance wire approximately incapaon the supporting wire. ble of selfsupport helically wound upon the While the Nuckols and Pruyn resistance insulating cord so as to stiffen the cord and has been successfully used, it has developed support the wire, said stiffened wire-supportobjectionable qualities which I have overing cord being formed into helical coils and come by the following means: Instead of mounted helically on said refractory core. the supporting wire which serves as the core 2. An electrical resistance comprising a reon which the bare fine wire is wound, I emfractory core, a coreless insulating cord, a

45 ploy a comparatively soft cord which is itbare resistance wire approximately incapable 

